The Research On Bacterioplankton Ecology In Coastal Water Of Qingdao In Shandong

The investigation of bacterioplankton in costal water of Qingdao were carried out on summer and winter in 2006 to count the cells quantity of total bacteria and community of heterotrophic bacteria, measure bacterial volume,and compute bacterial biomass in surface , intermediate and bottom water samples.The relation with environmental datas,which were used to study bacterial distribution and relationship of bacteria and ecological factors,make primary assessment of marine environmental quality.Main results as follows:The bacterial distribution in coastal water of Qingdao showed such a characteristic that the quantity in summer was more than that in winter,the density of bacteria decreased with the distance from the coast, and perpendicularity distributed inapparently.The range of heterotrophic bacteria community was 1.01×104～1.03×108 CFU/L.Heterotrophic bacteria scattered in sea aera mainly between the Dingzi bay and Laoshan bay in summer; in Jiaozhou Bay and its vicinity sea area in winter.Comparing the quantity of heterotrophic bacteria in different level of sea water in two seasons could get such result: surface water < intermediate water< bottom water. The range of total bacteria quantity,which is 9.76×108～9.6×109 cells/L,showed an obvious seasonal variation.Comparing the quantity of bacterioplankton in different level of sea water in summer could get such result:surface water< bottom water< intermediate water;and was different in winter:bottom water< intermediate water< surface water。The ecological factors that affecting bacterial distribution varied with seasons and levels of sea water. The quantity of heterotrophic bacteria displayed obvious relation with DO,TN,temperature,salinity,PH, activated phosphate, activated silicate,TOC,nitrate and Chla. The quantity of total bacteria displayed obvious relation with deepness,SS, PH,TN,TOC and virus. Bacterial biomass showed obvious relation with the quantity of total bacteria and bacterial volume,while had little relation with heterotrophic bacteria.The results of using the quantity of heterotrophic bacteria to assess marine environmental quality of Qingdao coastal water were as follows: 66.67%of the stations were moderate-polluted in winter and 53.33% of the stations were slightly-polluted in summer.The pollution in winter was more serious than that in summer,and the lower-pollution station were more far away from the shore. The ratio of the quantity of total bacteria to heterotrophic bacteria ,which were used to assess marine environmental quality of Qingdao coastal water,showing the similar results with the heterotrophic bacteria index, could reflect the pollution status,either. Assessment showed that Qingdao coastal water was in high eutrophication level in 2006,the pollution mainly came from land-sourced pollutants.